Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.9.3.1 (cytochrome oxidase)
 8,822 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

At present soluble NADP-dependent dehydrogenases are histochemically demonstrated in three different ways: according to the standard method incubation in aqueous media leads to the precipitation of formazan, the formation of which depends entirely on the presence of endogeneous NADPH2-tetrazolium reductases. With the two more recently established methods these reductases are by-passed with the use of intermediate electron acceptors incorporated in the medium. In addition, enzyme diffusion is inhibited either by an increased viscosity of the medium (PVA) or by a semipermeable membrane separating the medium from the section. Depending on the technique applied different distribution patterns have been described. By altering the concentrations of substrates, coenzyme, tetrazolium salt and cytochrome oxidase inhibitor, it was possible to improve both the PVA and membrane methods. Although similar results were obtained, because of its advantages the PVA method is recommended in this report and a detailed description is given. Using the latter for the demonstration of glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH), malic enzyme (ME) and isocitrate dehydrogenase (ICDH), characteristic distribution patterns were obtained in the liver parenchyma of male and female rats. For the first time a high G6PDH activity could be demonstrated in nonparenchymal cells which are mainly found in zone 1 of the liver acinus.
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PMID:NADP-dependent dehydrogenases in rat liver parenchyma. I. Methodological studies on the qualitative histochemistry of G6PDH, 6PGDH, malic enzyme and ICDH. 2 20

We have identified two distinct pools of superoxide dismutase in fractions of human peripheral neutrophils obtained by the isopycnic fractionation of homogenates of the latter with linear sucrose gradients. Superoxide dismutase activity, observed with polyacrylamide gels impregnated with Nitro Blue Tetrazolium, was present in: (1) the mitochondrial fraction [density (rho) 1.169g/ml], containing the high-molecular-weight KCN-resistant enzyme, and (2) the cytoplasm fraction, containing the low-molecular-weight KCN-sensitive enzyme. Superoxide dismutase activity, observed with a quantitative assay involving cytochrome c, was present in: (1) the mitochondria, (2) the cytoplasm, and (3) the azurophil-granule fractions (rho=1.206 and 1.222g/ml). No substantial enzyme activity was observed in specific-granule fractions (rho=1.187g/ml) or in the membranous fraction (rho=1.136g/ml) in either assay. The apparent superoxide dismutase activity observed in the azurophil granules with the cytochrome c assay was attributable not to true superoxide dismutase but to myeloperoxidase, an enzyme found solely in the azurophil granules. In the presence of H(2)O(2), human neutrophil myeloperoxidase oxidized ferrocytochrome c. Thus, in the cytochrome c assay for superoxide dismutase, the oxidation of ferrocytochrome c by myeloperoxidase mimicked the inhibition of reduction of ferricytochrome c by superoxide dismutase. When myeloperoxidase was removed from azurophilgranule fractions by specific immuno-affinity chromatography, both myeloperoxidase and apparent superoxide dismutase activities were removed. It is concluded that there is no detectable superoxide dismutase in either the azurophil or specific granules of human neutrophils. Mitochondrial superoxide dismutase, 15% of the total dismutase activity of the cells, occurred only in fractions of density 1.160g/ml, where isocitrate dehydrogenase and cytochrome oxidase were also observed.
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PMID:Subcellular distribution of superoxide dismutases in human neutrophils. Influence of myeloperoxidase on the measurement of superoxide dismutase activity. 19 57

Subepicardial and subendocardial arteries and arterioles in both the left and right normal canine ventricle were examined histochemically to determine their metabolic profiles. Aerobic metabolic capacity was assessed by determining the reactivities of the enzymes cytochrome oxidase, succinate dehydrogenase and NAD-isocitrate dehydrogenase. Glucose-6-phosphate dehydrogenase was examined to assess activity of the hexose-monophosphate-shunt. The substrate glycogen was determined as an evaluation of anaerobic metabolic capacity, while the amounts of deoxyribonucleic and ribonucleic acid were assessed as an indication of protein synthesis. Results of the present investigation indicate that despite known hemodynamic differences, the metabolic profile of the coronary vasculature is similar in all regions of ventricular myocardium. Reactivities of the enzymes succinate and NAD-isocitrate dehydrogenase and cytochrome oxidase are greater in smooth muscle of arterioles than in arteries. This suggests that arteriolar smooth muscle has a higher capacity for aerobic metabolism than does arterial smooth muscle. The greater reactivity of glycogen in arterial, than in arteriolar smooth muscle, suggests that arterial muscle is more adapted for anaerobic metabolism. Deoxyribonucleic and ribonucleic acids demonstrate a low reactivity in both arteries and arterioles from all regions of ventricular myocardium which conforms to the opinion that under normal conditions, coronary vasculature is quite stable with little cell proliferation. Glucose-6-phosphate dehydrogenase shows little reactivity in all myocardial vessels with implies a low capacity for nucleic acid and protein synthesis.
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PMID:A histochemical study of the microvasculature in the left and right cardiac ventricles of the dog. 21 88

The histochemical localization of some oxidoreductases was investigated in the epididymides of adult tomcats. Succinate dehydrogenase, lactate dehydrogenase, beta-hydroxybutyrate-dehydrogenase revealed their highest activity in corpus and cauda epididymidis whereas glucose-6-phosphate-dehydrogenase was strongest in the caput. The activity of the diaphorases and of cytochrome oxidase in the epididymal epithelium increased from caput towards the cauda epididymidis. The reaction for isocitrate dehydrogenase was distinct throughout the whole length of the ductus epididymidis. Our findings were compared with the biochemical results of other authors and the functions of the oxidoreductases in the epididymal epithelium were briefly discussed.
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PMID:[Enzyme histochemical studies on the epithelium of the epididymis of the tomcat (author's transl)]. 43 79

1. The distribution of 3 beta-hydroxy steroid dehydrogenase was examined in the subcellular fractions of granulosa cells collected from the ovary of the domestic fowl. 2. 3 beta-hydroxy steroid dehydrogenase activity was observed in the mitochondrial (4000g for 20min) and microsomal (105 000g for 120min) fractions. 3. Approximately three times more 3 beta-hydroxy steroid dehydrogenase activity was associated with the cytochrome oxidase activity (a mitochondrial marker enzyme) in anteovulatory-follicle granulosa cells than with that of the postovulatory follicle. 4. Comparison of the latent properties of mitochondrial 3 beta-hydroxy steroid dehydrogenase with those of cytochrome oxidase and isocitrate dehydrogenase indicated that 3 beta-hydroxy steroid dehydrogenase is located extramitochondrially. 5. This apparent distribution of 3 beta-hydroxy steroid dehydrogenase is explained on the basis that the mitochondrial activity is either an artefact caused by a redistribution in the subcellular location of the enzyme, occurring during homogenization, or by the existence of a functionally heterogeneous endoplasmic reticulum that yields particles of widely differing sedimentation properties.
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PMID:Subcellular distribution of delta 5-3 beta-hydroxy steroid dehydrogenase in the granulosa cells of the domestic fowl (Gallus domesticus). 51 48

Redox reactions were studied in 217 placentas obtained after partus maturus and pathological labor (premature labor, gestoses, incompatibility by Rh antigen, uterine inertia, placentas at early therapeutic and spontaneous abortions). Several uniform alterations were observed in activities of NADP-dependent isocitrate dehydrogenase, lactate-, glutamate- and malate dehydrogenases. Increase in the activity of these enzymes was accompanied by alteration in distribution of LDH isoenzymes and by elevated formation of glutamic acid; activities of transaminases, cytochrome c and cytochrome oxidase were unaltered. The alterations observed appear to be due to activation of compensatory-adaptive mechanisms of placenta.
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PMID:[Role of oxidative processes in the realization of the adaptive mechanisms of the human placenta]. 59 4

Male rats, aged 17 weeks at the end of experiments, were divided into four groups. Two groups lived in normal cage conditions with or without extra load (20% of the body weight) and two groups were trained by running with or without extra load for 8 weeks. Oxidation rates of succinate, glutamate + malate, palmitoylcarnitine, and pyruvate, and the activities of lactate dehydrogenase, citrate synthase, isocitrate dehydrogenase and cytochrome oxidase were measured in homogenates of the right ventricle and in those of the subendocardial and subepicardial layers of the left ventricle. Oxidation rates of succinate and palmitoylcarnitine tended to be higher in the subendocardium than in the subepicardium of sedentary control animals (p less than 0.1 and p less than 0.05, respectively). Transmural differences of succinate and palmitoylcarnitine oxidation rates were even more clear after running training (p less than 0.01 and p less than 0.05, respectively), after carrying extra load (p less than 0.001 and p less than 0.001, respectively) and after training carrying extra load (p less than 0.001 and p less than 0.05, respectively). Training also enhanced pyruvate oxidation rate in the subendocardium. Oxidation rates of all substrates were lower in the right ventricle than in the left ventricle. In control animals there were no regional differences in the myocardial enzyme activities and the training- or extra-load-induced changes were modest compared with the changes in the oxidation rates. The most significant change was the training-induced enhancement in the lactate dehydrogenase activity of the subendocardium (p less than 0.001 vs subepicardium). These results show greater subendocardial than subepicardial oxidation rates of certain substrates in the normal heart. These results also suggest that the myocardium adapts to increased work by increasing the subendocardial oxidation rate of some but not all substrates, indicating further that there may be qualitative mitochondrial differences in the different regions of the heart.
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PMID:Regional differences of substrate oxidation capacity in rat hearts: effects of extra load and endurance training. 207 98

Histochemical and histoenzymatic features of the adrenal medulla were studied 60 days after the end of an exposure to detergents. The findings obtained, point to an increase in the quantity of nucleic acids, and an intensified activity of nonspecific esterases as well as the cytochrome oxidase in rats maintained in a detergent manufacturing plant. The activity of isocitrate dehydrogenase was reduced in the control animals, as well as the activity of lactate dehydrogenase and isoenzyme "S" lactate dehydrogenase. The activity of isoenzyme "F" lactate dehydrogenase, glucose-6-phosphate dehydrogenase and succinate dehydrogenase is greater in the group which had been exposed to detergent influence. An active engagement of medullocytes is emphasized at this term of the experiment. The agent applied elicits a disturbance in the metabolism of glucose and a number of other substances. The author is of the opinion that an altered and stimulated synthesis and secretion of catecholamines takes place in the adrenal medullocytes under the experimental conditions which were investigated. The neuroendocrine system has been engaged in a series of processes which had been studied.
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PMID:[Histoenzymatic characteristics of the adrenal medulla 60 days after ending exposure to detergents]. 207 70

Patients treated for aneurysmal subarachnoid hemorrhage show, in the long-term follow up, an elevated rate of cognitive disturbances that are mainly related to the impact of the initial bleeding: the neurotoxic effects of blood deposition in subarachnoidal spaces may result in a diffuse encephalopathy, but the intrinsic mechanism and the biochemical correlates are not known. In the present study we have evaluated mitochondrial function after experimental induction of subarachnoid hemorrhage. Mitochondrial function was evaluated in four different rat brain areas (frontal cortex, occipital cortex, hippocampus, and brain stem) after experimental isobaric subarachnoid hemorrhage in rats. Subarachnoid hemorrhage was induced by injecting 0.07 mL of arterial autologous blood into the cisterna magna. Intracranial pressure did not significantly increase. The nonsynaptic mitochondrial fraction was isolated from different rat brain areas, and the maximal rate of enzymatic reactions of some key enzymatic activities related to the Krebs cycle [nicotinamide adenine dinucleotide (oxidized form) (NAD+)-isocitrate dehydrogenase, citrate synthase, and succinate dehydrogenase] and of the electron transfer chain (cytochrome oxidase) were evaluated. The nonsynaptic mitochondrial fraction was utilized also to check parameters related to the mitochondrial respiration: state 3, state 4, uncoupled state, respiratory control ratio, and adenosine 5'-diphosphate/oxygen ratio. The biochemical parameters were measured at 1 and 72 hours after the subarachnoidal injection of blood. Subarachnoid hemorrhage did not affect the mitochondrial enzymatic activities both at 1 and 72 hours, while the mitochondrial enzymatic activities parameters were significantly affected: in particular, a significant decrease of respiratory control ratio in all tested brain areas was demonstrated. The increased mitochondrial vulnerability in the delayed phases could be one of the biochemical correlates of post-hemorrhagic encephalopathy.
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PMID:Experimental isobaric subarachnoid hemorrhage: regional mitochondrial function during the acute and late phase. 221 48

The in vitro metabolism of [1-13C]glucose by Ascaris suum third and fourth-stage larvae was analyzed under different gas phases using 13C nuclear magnetic resonance spectroscopy (13C-NMR). Third-stage larvae (L3) incubated under a gas phase of 85% N2/5% O2/10% CO2 produced trace amounts of [13C]succinate, and molted to fourth-stage larvae (L4) between days 3 and 4 in vitro. However, they appeared to arrest as L3s when incubated under air, or 85% N2/5% O2/10% CO2 in the presence of 2 mM potassium cyanide, or 95% N2/5% CO2. Day 12 L4 (eight days after molting) incubated under 85% N2/5% O2/10% CO2, or 95% N2/5% CO2, or 94% N2/1% O2/5% CO2, produced succinate, acetate, propionate and the branched-chain fatty acids 2-methylvalerate and 2-methylbutyrate by fermentative pathways characteristic of adult body wall muscle. In contrast, when Day 12 L4 were incubated under air, only trace amounts of these acids were detected in the incubation medium. Thus, L4 are capable of synthesizing end-products typical of the adult even in the presence of oxygen, as long as the CO2 tensions are above 5%. As would be predicted, activities of enzymes involved in aerobic metabolism, including citrate synthase, isocitrate dehydrogenase, and cytochrome oxidase, decreased dramatically as L4s underwent the final ecdysis and matured to the adult stage. More importantly, activities of enzymes typical of anaerobic metabolism, including phosphoenolpyruvate carboxykinase and malic enzyme, were substantially elevated in L3s (over their levels in second-stage larvae), and appeared to have reached their adult levels in L3s prior to the third molt, even though L3s still exhibited cyanide sensitivity. Since L3s and L4s have enzymes involved in both aerobic and anaerobic pathways, it is possible that the L3s contain two populations of mitochondria, one which functions aerobically and a second which functions anaerobically.
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PMID:Effect of gas phase on carbohydrate metabolism in Ascaris suum larvae. 250 8


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